Complex Trichinella spiralis

Trichinellosis is caused by the parasitic nematode Trichinella spiralis. This parasite has a complex life cycle that alternates between intestinal and muscle cell compartments of the host. This nematode infection is unusual because 7. spiralis is an intracellular parasite of mammalian cells. In addition, the broad host range of this parasite includes most mammals. The disease in humans has intrigued parasitologists, other biologists and public health workers for over a century (Cambell, 1983). The attraction to trichinellosis pardy stems from the debilitating and sometimes fatal effects that characterize this disease. 

Lindh, J.G., Connolly, B., McGhie, D.L. and Smith, D.F. (1998) Identification of a developmentally regulated Trichinella spiralis protein that inhibits MyoD-specific protein DNA complexes in vitro. Molecular and Biochemical Parasitology 92,163-175. 

Yao, C. and Jasmer, D.P. (1998) Nuclear antigens in Trichinella spiralis infected muscle cells nuclear extraction, compartmentalization and complex formation. Molecular and Biochemical Parasitology 92, 207—218. 

Vallance, B.A., Galeazzi, F., Collins, S.M. and Snider, D.P. (1999b) CD4 T cells and major histocompatibility complex class II expression influence worm expulsion and increased intestinal muscle contraction during Trichinella spiralis infection. Infection and Immunity 67, 6090-6097. 

TS, DHFR and dUTPase were found to be persistently expressed at a high and constant level, comparable to that found in regenerating rat liver, in crude extracts from adult worms of Trichinella spiralis, as well as from developmentaUy arrested muscle larvae of both Trichinella spiralis (isolated 1-24 months after infection) and Trichinella pseudospiralis (isolated 5.5-13 months after infection). The results obtained with Trichinella pseudospiralis muscle larvae isolated with the use of pepsin did not differ from those obtained when pepsin was not used. Moreover, T. spiralis muscle larvae (T pseudospiralis larvae were not tested) contained also high level, comparable with that found in mouse leukemia LI210 cells, of DNA polymerase a, a key enzyme of the eukaryotic replication complex, its expression also known to be associated with cell proliferation. 

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